Fabrication and electrochemical characteristics of all- solid-state lithium-ion batteries using V2O5 thin films for both electrodes

An all-solid-state lithium-ion cell consisting of two types of vanadium oxide electrodes and a lithium phosphorous oxynitride electrolyte has been developed. A thin-film type rechargeable battery was fabricated by a radio-frequency (rf) magnetron sputtering under Ar gas from a V2O5 target and under N-2 gas from a Li3PO4 target. The cell had a typical open-circuit voltage of 3.5-3.6 V and a discharge capacity of about 6 mu Ah/cm(2) at a current density of 10 mu Ah/cm(2) when discharged down to 1.0 V. The battery also exhibited relatively good cycling and self-discharge performances, typically above 350 cycles and 0.079 V/month (roughly equivalent to a capacity percentage of 2.3%, and a self-discharge current of 4.8 x 10(-4) mAh/cm(2)) at steady state, respectively. Because the cell contained only two kinds of inorganic materials prepared by rf magnetron sputtering, a simple, compact and heat-durable dry cell with good reliability was realized in a completely solid-state and thin-film configuration. (C) 1999 The Electrochemical Society. S1099-0062(99)01-108-6. All rights reserved.